# Rugged **libgit2 bindings in Ruby** Rugged is a library for accessing [libgit2](https://github.com/libgit2/libgit2) in Ruby. It gives you the speed and portability of libgit2 with the beauty of the Ruby language. ### libgit2 libgit2 is a pure C implementation of the Git core methods. It's designed to be fast and portable. For more information about libgit2, [check out libgit2's website](http://libgit2.github.com) or browse the [libgit2 organization](https://github.com/libgit2) on GitHub. ## Install Rugged is a self-contained gem. You can install it by running: $ gem install rugged You need to have CMake and `pkg-config` installed on your system to be able to build the included version of `libgit2`. On OS X, after installing [Homebrew](http://brew.sh/), you can get CMake with: ```bash $ brew install cmake ``` If you want to build Rugged with HTTPS and SSH support, check out the list of optional [libgit2 dependencies](https://github.com/libgit2/libgit2#optional-dependencies). If you're using bundler and want to bundle `libgit2` with Rugged, you can use the `:submodules` option: ```ruby gem 'rugged', git: 'git://github.com/libgit2/rugged.git', branch: 'development', submodules: true ``` To load Rugged, you'll usually want to add something like this: ```ruby require 'rugged' ``` ### Use the system provided libgit2 By default, Rugged builds and uses a bundled version of libgit2. If you want to use the system library instead, you can install rugged as follows: ``` gem install rugged -- --use-system-libraries ``` Or if you are using bundler: ``` bundle config build.rugged --use-system-libraries bundle install ``` However, note that Rugged does only support specific versions of libgit2. ## Usage Rugged gives you access to the many parts of a Git repository. You can read and write objects, walk a tree, access the staging area, and lots more. Let's look at each area individually. ### Repositories #### Instantiation The repository is naturally central to Git. Rugged has a `Repository` class that you can instantiate with a path to open an existing repository : ```ruby repo = Rugged::Repository.new('path/to/my/repository') # => # ``` You can create a new repository with `init_at`. Add a second parameter `:bare` to make a bare repository: ```ruby Rugged::Repository.init_at('.', :bare) ``` You can also let Rugged discover the path to the .git directory if you give it a subdirectory. ```ruby Rugged::Repository.discover("/Users/me/projects/repo/lib/subdir/") # => "/Users/me/projects/repo/.git/" ``` Once your Repository instantiated (in the following examples, as `repo`), you can access or modify it. #### Accessing a Repository ```ruby # Does the given SHA1 exist in this repository? repo.exists?('07b44cbda23b726e5d54e2ef383495922c024202') # => true # Boolean repository state values: repo.bare? # => false repo.empty? # => true repo.head_unborn? # => false repo.head_detached? # => false # Path accessors repo.path # => "path/to/my/repository/.git/" repo.workdir # => "path/to/my/repository/" # The HEAD of the repository. ref = repo.head # => #}> # From the returned ref, you can also access the `name`, `target`, and target SHA: ref.name # => "refs/heads/master" ref.target # => #}> ref.target_id # => "2bc6a70483369f33f641ca44873497f13a15cde5" # Reading an object object = repo.read('a0ae5566e3c8a3bddffab21022056f0b5e03ef07') # => # object.len # => 237 object.data # => "tree 76f23f186076fc291742816721ea8c3e95567241\nparent 8e3c5c52b8f29da0adc7e8be8a037cbeaea6de6b\nauthor Vicent Mart\303\255 1333859005 +0200\ncommitter Vicent Mart\303\255 1333859005 +0200\n\nAdd `Repository#blob_at`\n" object.type # => :commit ``` #### Writing to a Repository There's a few ways to write to a repository. To write directly from your instantiated repository object: ```ruby sha = repo.write(content, type) ``` You can also use the `Commit` object directly to craft a commit; this is a bit more high-level, so it may be preferable: ```ruby oid = repo.write("This is a blob.", :blob) index = repo.index index.read_tree(repo.head.target.tree) index.add(:path => "README.md", :oid => oid, :mode => 0100644) options = {} options[:tree] = index.write_tree(repo) options[:author] = { :email => "testuser@github.com", :name => 'Test Author', :time => Time.now } options[:committer] = { :email => "testuser@github.com", :name => 'Test Author', :time => Time.now } options[:message] ||= "Making a commit via Rugged!" options[:parents] = repo.empty? ? [] : [ repo.head.target ].compact options[:update_ref] = 'HEAD' Rugged::Commit.create(repo, options) ``` --- ### Objects `Object` is the main object class - it shouldn't be created directly, but all of these methods should be useful in their derived classes. ```ruby obj = repo.lookup(sha) obj.oid # object sha obj.type # One of :commit, :tree, :blob or :tag robj = obj.read_raw str = robj.data int = robj.len ``` There are four base object types in Git: **blobs**, **commits**, **tags**, and **trees**. Each of these object types have a corresponding class within Rugged. ### Commit Objects ```ruby commit = repo.lookup('a0ae5566e3c8a3bddffab21022056f0b5e03ef07') # => # commit.message # => "Add `Repository#blob_at`\n" commit.time # => Sat Apr 07 21:23:25 -0700 2012 commit.author # => {:email=>"tanoku@gmail.com", :name=>"Vicent Mart\303\255", :time=>Sun Apr 08 04:23:25 UTC 2012} commit.tree # => # commit.parents # => [#] ``` You can also write new objects to the database this way: ```ruby author = {:email=>"tanoku@gmail.com", :time=>Time.now, :name=>"Vicent Mart\303\255"} Rugged::Commit.create(r, :author => author, :message => "Hello world\n\n", :committer => author, :parents => ["2cb831a8aea28b2c1b9c63385585b864e4d3bad1"], :tree => some_tree, :update_ref => "HEAD") #=> "f148106ca58764adc93ad4e2d6b1d168422b9796" ``` ### Tag Objects ```ruby tag = repo.lookup(tag_sha) object = tag.target sha = tag.target.oid str = tag.target_type # :commit, :tag, :blob str = tag.name # "v1.0" str = tag.message person = tag.tagger ``` ### Tree Objects ```ruby tree = repo.lookup('779fbb1e17e666832773a9825875300ea736c2da') # => # # number of tree entries tree.count tree[0] # or... tree.first # or... tree.get_entry(0) # => {:type=>:blob, :oid=>"99e7edb53db9355f10c6f2dfaa5a183f205d93bf", :filemode=>33188, :name=>".gitignore"} ``` The tree object is an Enumerable, so you can also do stuff like this: ```ruby tree.each { |e| puts e[:oid] } tree.sort { |a, b| a[:oid] <=> b[:oid] }.map { |e| e[:name] }.join(':') ``` And there are some Rugged-specific methods, too: ```ruby tree.each_tree { |entry| puts entry[:name] } # list subdirs tree.each_blob { |entry| puts entry[:name] } # list only files ``` You can also write trees with the `TreeBuilder`: ```ruby oid = repo.write("This is a blob.", :blob) builder = Rugged::Tree::Builder.new builder << { :type => :blob, :name => "README.md", :oid => oid, :filemode => 0100644 } options = {} options[:tree] = builder.write(repo) options[:author] = { :email => "testuser@github.com", :name => 'Test Author', :time => Time.now } options[:committer] = { :email => "testuser@github.com", :name => 'Test Author', :time => Time.now } options[:message] ||= "Making a commit via Rugged!" options[:parents] = repo.empty? ? [] : [ repo.head.target ].compact options[:update_ref] = 'HEAD' Rugged::Commit.create(repo, options) ``` ### Blob Objects Blob objects represent the data in the files of a Tree Object. ```ruby blob = repo.lookup('e1253910439ea902cf49be8a9f02f3c08d89ac73') blob.content # => Gives you the content of the blob. ``` #### Streaming Blob Objects There is currently no way to stream data from a blob, because `libgit2` itself does not (yet) support streaming blobs out of the git object database. While there are hooks and interfaces for supporting it, the default file system backend always loads the entire blob contents into memory. If you need to access a Blob object through an IO-like API, you can wrap it with the `StringIO` class. Note that the only advantage here is a stream-compatible interface, the complete blob object will still be loaded into memory. Below is an example for streaming a Blob using the Sinatra framework: ```ruby # Sinatra endpoint get "/blobs/:sha" do repo = Rugged::Repository.new(my_repo_path) blob = repo.lookup params[:sha] headers({ "Vary" => "Accept", "Connection" => "keep-alive", "Transfer-Encoding" => "chunked", "Content-Type" => "application/octet-stream", }) stream do |out| StringIO.new(blob.content).each(8000) do |chunk| out << chunk end end end ``` --- ### Commit Walker `Rugged::Walker` is a class designed to help you traverse a set of commits over a repository. You first push head SHAs onto the walker, and then call next to get a list of the reachable commit objects one at a time. You can also `hide()` commits if you are not interested in anything beneath them (useful in situations like when you're running something like `git log master ^origin/master`). ```ruby walker = Rugged::Walker.new(repo) walker.sorting(Rugged::SORT_TOPO | Rugged::SORT_REVERSE) # optional walker.push(hex_sha_interesting) walker.hide(hex_sha_uninteresting) walker.each { |c| puts c.inspect } walker.reset ``` --- ### Index ("staging") area We can inspect and manipulate the Git Index as well. To work with the index inside an existing repository, instantiate it by using the `Repository.index` method instead of manually opening the Index by its path. ```ruby index = Rugged::Index.new(path) # Re-read the index file from disk. index.reload # Count up index entries. count = index.count # The collection of index entries. index.entries # Iterating over index entries. index.each { |i| puts i.inspect } # Get a particular entry in the index. index[path] # Unstage. index.remove(path) # Stage. Also updates existing entry if there is one. index.add(ientry) # Stage. Create ientry from file in path, updates the index. index.add(path) ``` --- ### Refs You can access references through the `Rugged::ReferenceCollection` object returned by `Repository#references`. ```ruby ref = repo.references["refs/heads/master"] sha = ref.target_id str = ref.type # :direct str = ref.name # "refs/heads/master" ``` You can also easily iterate over all references: ```ruby repo.references.each do |ref| puts ref.name end ``` Or only over references that match the given pattern (glob): ```ruby repo.references.each("refs/tags/*") do |ref| puts ref.name end ``` It is also easy to create, update, rename or delete a reference: ```ruby ref = repo.references.create("refs/heads/unit_test", some_commit_sha) repo.references.update(ref, new_sha) # or... repo.references.update("refs/heads/unit_test", new_sha) repo.references.rename(ref, "refs/heads/blead") # or... repo.references.rename("refs/heads/unit_test", "refs/heads/blead") repo.references.delete(ref) # or... repo.references.delete("refs/heads/unit_test") # or... ``` Finally, you can access the reflog for any branch: ```ruby ref = repo.references["refs/heads/master"] entry = ref.log.first sha = entry[:id_old] sha = entry[:id_new] str = entry[:message] prsn = entry[:committer] ``` --- ### Branches The `Rugged::BranchCollection` object returned by `Repository#branches` will help you with all of your branch-related needs. Iterate over all branches: ```ruby repo.branches.each_name().sort # => ["master", "origin/HEAD", "origin/master", "origin/packed"] repo.branches.each_name(:local).sort # => ["master"] repo.branches.each_name(:remote).sort # => ["origin/HEAD", "origin/master", "origin/packed"] ``` Look up branches and get attributes: ```ruby branch = repo.branches["master"] branch.name # => 'master' branch.canonical_name # => 'refs/heads/master' ``` Look up the id for the target of a branch: ```ruby repo.branches["master"].target_id # => "36060c58702ed4c2a40832c51758d5344201d89a" ``` Creation and deletion: ```ruby branch = repo.branches.create("test_branch", "HEAD") repo.branches.rename("test_branch", "new_branch") # or... repo.branches.rename("refs/heads/test_branch", "new_branch") # or... repo.branches.rename(ref, "new_branch") # or... repo.branches.delete("test_branch") # or... repo.branches.delete("refs/heads/test_branch") # or... repo.branches.delete(ref) # or... ``` --- ### Diffs There are various ways to get hands on diffs: ```ruby # Diff between two subsequent commits diff_commits = commit_object.parents[0].diff(commit_object) # Diff between two tree objects diff_trees = tree_object_a.diff(tree_object_b) # Diff between index/staging and current working directory diff_index = repository.index.diff # Diff between index/staging and another diffable (commit/tree/index) diff_index_diffable = repository.index.diff(some_diffable) ``` When you already have a diff object, you can examine it: ```ruby # Get patch diff.patch => "diff --git a/foo1 b/foo1\nnew file mode 100644\nindex 0000000..81b68f0\n--- /dev/null\n+++ b/foo1\n@@ -0,0 +1,2 @@\n+abc\n+add line1\ndiff --git a/txt1 b/txt1\ndeleted file mode 100644\nindex 81b68f0..0000000\n--- a/txt1\n+++ /dev/null\n@@ -1,2 +0,0 @@\n-abc\n-add line1\ndiff --git a/txt2 b/txt2\nindex a7bb42f..a357de7 100644\n--- a/txt2\n+++ b/txt2\n@@ -1,2 +1,3 @@\n abc2\n add line2-1\n+add line2-2\n" # Get delta (faster, if you only need information on what files changed) diff.each_delta{ |d| puts d.inspect } #"0000000000000000000000000000000000000000", :path=>"foo1", :size=>0, :flags=>6, :mode=>0}, new_file: {:oid=>"81b68f040b120c9627518213f7fc317d1ed18e1c", :path=>"foo1", :size=>14, :flags=>6, :mode=>33188}, similarity: 0, status: :added> #"81b68f040b120c9627518213f7fc317d1ed18e1c", :path=>"txt1", :size=>14, :flags=>6, :mode=>33188}, new_file: {:oid=>"0000000000000000000000000000000000000000", :path=>"txt1", :size=>0, :flags=>6, :mode=>0}, similarity: 0, status: :deleted> #"a7bb42f71183c162efea5e4c80597437d716c62b", :path=>"txt2", :size=>17, :flags=>6, :mode=>33188}, new_file: {:oid=>"a357de7d870823acc3953f1b2471f9c18d0d56ea", :path=>"txt2", :size=>29, :flags=>6, :mode=>33188}, similarity: 0, status: :modified> # Detect renamed files # Note that the status field changed from :added/:deleted to :renamed diff.find_similar! diff.each_delta{ |d| puts d.inspect } #"81b68f040b120c9627518213f7fc317d1ed18e1c", :path=>"txt1", :size=>14, :flags=>6, :mode=>33188}, new_file: {:oid=>"81b68f040b120c9627518213f7fc317d1ed18e1c", :path=>"foo1", :size=>14, :flags=>6, :mode=>33188}, similarity: 100, status: :renamed> #"a7bb42f71183c162efea5e4c80597437d716c62b", :path=>"txt2", :size=>17, :flags=>6, :mode=>33188}, new_file: {:oid=>"a357de7d870823acc3953f1b2471f9c18d0d56ea", :path=>"txt2", :size=>29, :flags=>6, :mode=>33188}, similarity: 0, status: :modified> # Merge one diff into another (mutating the first one) diff1.merge!(diff2) # Write a patch into a file (or any other object responding to write) # Note that the patch as in diff.patch will be written, it won't be applied file = File.open('/some/file', 'w') diff.write_patch(file) file.close ``` --- ### Config files It's also easy to read and manipulate the Git config file data with Rugged. ```ruby # Read values repo.config['core.bare'] # Set values repo.config['user.name'] = true # Delete values repo.config.delete('user.name') ``` --- ### General methods Rugged also includes a general library for handling basic Git operations. One of these is converting a raw sha (20 bytes) into a readable hex sha (40 characters). ```ruby Rugged.hex_to_raw('bfde59cdd0dfac1d892814f66a95641abd8a1faf') # => "\277\336Y\315\320\337\254\035\211(\024\366j\225d\032\275\212\037\257" Rugged.raw_to_hex("\277\336Y\315\320\337\254\035\211(\024\366j\225d\032\275\212\037\257") => "bfde59cdd0dfac1d892814f66a95641abd8a1faf" ``` --- ## Contributing Fork libgit2/rugged on GitHub, make it awesomer (preferably in a branch named for the topic), send a pull request. ## Development Simply clone and install: $ git clone https://github.com/libgit2/rugged.git $ cd rugged $ bundle install $ rake compile $ rake test ## Support We encourage you to use StackOverflow for any questions or concerns regarding Rugged. Please tag your questions with the [rugged](http://stackoverflow.com/questions/tagged/rugged) keyword. For bug reports, please open a ticket on the GitHub [issue tracker](https://github.com/libgit2/rugged/issues). ## Authors * Vicent Marti * Scott Chacon * Arthur Schreiber ## License MIT. See LICENSE file.